It is known to use known drainage apparatus to eliminate condensate from pressurized air systems. When air is compressed there is a normal resulting moisture or condensate which, if allowed to remain in the system, could cause damage and corrosion in the system. In high volume or capacity applications, large amounts of moisture are formed which must be constantly drained and discharged from the assemblage. Preferably, an automatic drain is used to avoid over-accumulation of water and to allow the pressurized system to function properly.
There are various float valve assemblies presently used to remove condensed moisture from compressed air systems. Some are described in U.S. Pat. Nos. 4,444,217; 4,562,855; 4,574,829; 4,779,640; 5,004,004 and 5,014,735, all issued to E. W. Cummings or E. W. Cummings et al; hereinafter "Cummings patents". A further float type drain for condensed air systems is disclosed in U.S. Pat. No. 5,080,126 to DeRycke.
In the Cummings patents, various automatic drain traps are disclosed, each differing in structure but similar in function. Some of the Cummings patents disclose float activated water discharge systems and others of various configurations. Drain-All Inc. of P.O. Box 609, Louisville, Tenn. 37777 markets a compressed air drain similar to those disclosed in some of the Cummings patents. These Drain-All apparatus require the use of a large float to give buoyancy to a relatively large and heavy magnet. Any large size float in any system will take up a large amount of space in the liquid reservoir. This reduces the amount of liquid that can be drained per cycle. If it is desired in these prior art systems to drain more condensation, the size of the vessel would have to be enlarged to provide a larger reservoir. To do this, the device weight would have to be increased with the resulting disadvantages associated with this. These prior art devices most or all require the use of a vent line on all applications. The vent line is required to let the displaced air in the system escape as the water enters the reservoir. Vents are required when the condensation enters from the bottom of the reservoir such as in these prior art devices. An advantage of using a bottom only entry port is to keep any metal scale from attaching itself to the large magnet of the prior art units.
In the DeRycke patent a float controlled valve is also used to discharge moisture in a compressed air system. In apparatus similar to DeRycke's, a poppet valve is used which often will not seat properly when scale and other particulate matter is ejected from the system. These prior art devices usually have five pivot points. The large number of pivot points and the use of two seats and two magnets increase the chance of failure due to wear or misalignment of these complex designs. Also, in similar prior art structures, two of the pivot points are likely to be submerged in condensation during normal operation. One of the elements commonly contained in condensation is oil which floats on top of water. This oil will thicken and coat surfaces with varnish. The result will increase the possibility that the two pivot points could bind and cause a failure.
There is therefore a need for a further improved and efficient system for removing moisture from condensed air systems.